Portion of an elbow for a respiratory mask



FIG. 1 is a front perspective view of a portion of an elbow for a respiratory mask according to our design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

Where included, broken lines showing environment or structure are for illustrative purposes only and form no part of the claimed design. Where included, dotted lines represent the border between claimed and unclaimed subject matter and form no part of the claimed design. 

The ornamental design for a portion of an elbow for a respiratory mask, as shown and described. 